SITE INFORMATION AND CORRESPONDENCE

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Ms.Lori Duncan January 19,2011 RE: 2911 E.Fremont St,Stockton,CA Page 3 of 6 Fisch advanced the borings to depths between 36.3 and 42.5 feet below ground surface(bgs), utilizing 2.25-inch diameter drill rods, which were fitted with clear acetate sleeves to allow continuous core sampling. Soil samples were collected using a 1.25-inch diameter core sampler lined with clear acetate sleeves. Soil was characterized by L&P personnel in using the Unified Soil Classification System (USCS) and for evidence of contamination. Soil samples selected for analysis were sealed with Teflon tape and plastic end caps,labeled,placed in a pre-cooled ice chest. Cored soil samples not submitted to the laboratory were placed in a 55-gallon drum and remain on site pending characterization for disposal. Groundwater samples were collected using a push-point groundwater sampler. The samples were collected by driving the sampler to the desired depth and exposing the screen to the formation. The groundwater samples were collected using a length of 0.17 inner diameter tubing equipped with a stainless steel bottom check valve. The tubing was inserted through the probe rods and connected to the sampler at the desired depth. The groundwater samples were brought to the surface by gripping the top of the tubing and rapidly moving the tubing up and down creating a positive displacement effect, thereby forcing the water sample to the surface where it was collected directly into the sample containers. Soil and water samples were transported under chain of custody to Argon Laboratories, Inc., a State certified analytical laboratory(California D.O.H.S. Certification#2359). Fisch sealed the borings with neat cement grout utilizing a tremie pipe after sampling was completed. Field Observations Soil beneath the site consisted primarily of silts and clays from the ground surface to 26-28 feet bgs,silty sand to sandy silt from approximately 26-28 to approximately 32 feet bgs, and silt and clay from approximately 32 to 40 feet bgs. Silty sand was present in borings LPB-1 and LPB-3, located approximately 3 feet north and 15 feet west of the clarifier,respectively,at a depth of approximately 40 feet bgs. In addition, silty sand was more prevalent in boring LPB-3 (between 19 and 23 feet and 32 and 37 feet bgs)than in other site borings. The maximum depth of the borings ranged from approximately 36.3 feet in LPB-3 to approximately 42.5 feet in the other borings. Moderate petroleum odors were observed in boring LPB-1, located within several feet of the clarifier, from approximately 5 feet bgs to approximately 32 feet, and slight odors were noted between approximately 32 and 39 feet bgs. No odors were noted in any other boring. Although rod refusal was encountered prior to reaching groundwater using the 2.25-inch diameter rods,a small diameter groundwater sampler was advanced at each location to allow for collection of groundwater samples. Based upon the driller's observations, groundwater was encountered at a depth of approximately 55 feet bgs in each of the borings,and groundwater samples were collected as described in the previous section of this report. Attachment 1 contains copies of the soil boring logs. 10759-SUMMARY LTR